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Dr. F., having been driven to sheer unholy madness by the mendacity, folly, and criminality of the Bush Administration, not to mention the uncouth, ungrammatical, and vacuous rhetoric of its principal, has retreated to a better but imaginary world.

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Monday, February 28, 2011

Good theories and bad can be distinguished by the biblical prescription. By their fruits you shall know them. Good theories lead to discoveries. Bad theories just lead to more theories designed to save the old bad theories.

How do we tell if we are dreaming or not? The problem is that in dreams our critical faculties are more than a little attenuated. In a dream it may seem plausible that one has suddenly become wildly attractive to hot nineteen year-old coeds, or (as in my case) that my lifelong dream of flying under mental power has finally been achieved.

So there I was, sitting on the edge of a roof to which I believed I had just flown. Dare I launch into space to fly down?

In the movie Inception the protagonist carries a little top to test dream vs. reality - if it doesn't stop, it's supposed to be dreamland. Well, I didn't have a top, and it wouldn't have stayed on the slanted roof anyway, but I did recall another idea: supposedly counting your fingers is a good test of dream vs. reality. I looked at my hand. At a glance, it certainly seemed to have the right number of fingers.

I began to count: one, two, three...but then the last two - or was it three - seemed to kind of blur together, and I really couldn't tell if I had counted them already or not. I tried it a few times, always with the same result.

Sunday, February 27, 2011

The most shocking thing about the New Zealand quake is the large number of casualties from what seemed like a relatively small quake. The total energy in the NZ quake was about 6000 times smaller than the big 2010 quake in Chile, yet the causualty figures are comparable, and this despite the fact that New Zealand is a first world country with very tough building codes.

Location seems to be a critical factor. The NZ quake was both near and shallow, both aggravating circumstances, but I expect that they will be taking a closer look at those building standards for the future.

Big government, by the way, seems to be an essential feature in coping with natural disasters. Building codes play a critical role in surviving floods, quakes, and related calamities. We saw Bush's small government philosophy in full swing in the Katrina disaster, where thousands of Americans died mostly due to governmental incompetence. The very same year, miserably poor and grossly misruled Cuba survived even more devastating Hurricanes with very few deaths.

Mathematicians have been known to note a certain type of relationship, their Erdös numbers and for movie stars there are degrees of Kevin Bacon. We may define a similar number for chess players – the number of steps we need to go through to find a player who played us who played somebody (or chain of somebodies) who played the target. My Bobby Fisher number is two, as is my Alexander Alekhine number, since I have played chess players who played each of them. Via Fisher and Alekhine and a few others, I have second or third degree connections with most of the other twentieth century World Chess Champions.

This, of course, doesn’t make me any less of a fish = weakie chess player.

While playing in some kind of (bridge?) tournament when I was in the Army, I met another soldier who played chess, and we decided to form a chess team. He turned out to be a very strong player (a former national junior champion), and was acquainted with our mutual contemporary, Fisher. I think that they had been to some international junior tournaments together. He used to say “I beat Bobby Fisher once” – pausing before adding – “at miniature golf.” He was my link to Fisher.

Since he was a psychologist, I often discussed Fisher’s pathology (already evident in those nine or ten years pre-world championship) with him.

Reading about Fisher lately, I thought back on him and decided to look him up on the internet. It turned out that he had been a psychology professor for some thirty years, so I suspect he might have had more to add to the story – unfortunately, the source in which I encountered that information turned out to be his obituary. Like Fisher, and an increasing number of my contemporaries, he has passed beyond this particular vale.

Andrew Sullivan notes that Obama cooly waited until Americans were out of Libya before harshly condemning Gaddafi. He compares this behavior favorably to that of some notorious blowhards and hip shooters. Leon Wieseltier is his poster boy for the latter.

Saturday, February 26, 2011

Civilization, and life in general, can be thought of as being powered by negative entropy. We need to get low entropy energy from somewhere, extract some useful work from it, and dump the resulting high entropy energy into some cool reservoir. For living systems, this usually amounts to Gibbs Free Energy, but our machines are less picky.

Except for little bits of nuclear energy stored in our rocks by ancient supernovae, and a tiny bit from various gravitational sources (tides, continuing contraction of the Earth) all that energy comes from the Sun. Three and a half billion years or so ago, certain autotrophs learned how capture a photon and hook up its energy to power some chemical reactions to store energy C. We could plausibly call this the most important invention in the history of life. All told, such reactions capture roughly 100 terawatts of solar power.

Heterotrophs, like us, evolved to consume those autotrophs and get our (Gibbs) free energy from them. As Eli has noted, we humans are approximately 100 watt machines, and since the process of autotrophs turning sunlight into us isn't perfectly efficient, it takes quite a bit more than 100 tera watts of sunlight to keep one of us fed - a lot more if most of it is processed through animals before getting to us.

Our remote ancestors collected their 100 watts (plus, since they led active lives) by gathering roots, berries, insects, carrion, and whatever animals they could catch. Our first great inventions, tools, fire, and language, enabled us to become more efficient at collecting food and extracting nutrition from it. Those inventions were enough to turn us from a minor East African plains ape into a species indigenous to much of the world, but population densities remained extremely low by modern standards - fewer people in the whole world than there are now in one fairly big city.

If there were five million people then, each consuming (say) a net of 600 Watts counting, fire, plant and animal food, the total consumption would be just 3 GigaWatts - or about 3 parts in 100,000 of the total.

The invention of horticulture allowed us to concentrate plants that we could eat, and domestication of animals allowed us to consume (indirectly) a wider variety of plants. We multiplied in numbers in return for which we got to work harder and be much less well nourished.

Currently there are seven billion of us, and an average American uses about 11.4 kilo watts of power. If we all lived as large as an average American, that would amount to 80 tera watts - or nearly every bit of energy life captures from the Sun.

That's not possible, of course, so instead we spend the energy the planet stored up over the past billion years or so.

Thursday, February 24, 2011

Now that Charlie Sheen seems to have trashed his show (Two and a Half Men), maybe Chuck Lorre's operation can devote more top writers to The Big Bang Theory, where the writing has looked a bit thin since Lorre added the show about the chubbies.

I imagine that Sheen has now pretty much stamped "permanent loser" on his own forehead. Too bad, because he had talent and looks. Who is likely to take a chance on him now?

The Obama Administration has been consistently caught flatfooted in the wave of rebellions sweeping through the North Africa. There was probably more excuse in the case of Tunisia and Egypt, where the governments went with relatively little violence. Lybia is not like that. There was plenty of forewarning and Obama still can't even condemn Quaddafi by name.

At a minimum, a show of force and harsh warning would be appropriate - are there any carriers close by?

A group of NBA point guards once critiques the President's basketball. Magic Johnson gave him the ultimate praise - saying he was always thinking 5 minutes ahead. Five minutes is a lot on the hard court but not nearly enough in the hard world.

In particular, Obama better be ready when the wave hits Saudi Arabia. In my opinion he ought to tell them that he is with them for reasonable attempts to reform their repressive state, but count us on the other side if they start shooting their own people ala Gaddafi.

Monday, February 21, 2011

Among the thousands of demonstrators who jammed the Wisconsin State Capitol grounds this weekend was a well-financed advocate from Washington who was there to voice praise for cutting state spending by slashing union benefits and bargaining rights.

The visitor, Tim Phillips, the president of Americans for Prosperity, told a large group of counterprotesters who had gathered Saturday at one edge of what otherwise was a mostly union crowd that the cuts were not only necessary, but they also represented the start of a much-needed nationwide move to slash public-sector union benefits.

“We are going to bring fiscal sanity back to this great nation,” he said.

What Mr. Phillips did not mention was that his Virginia-based nonprofit group, whose budget surged to $40 million in 2010 from $7 million three years ago, was created and financed in part by the secretive billionaire brothers Charles G. and David H. Koch.

State records also show that Koch Industries, their energy and consumer products conglomerate based in Wichita, Kan., was one of the biggest contributors to the election campaign of Gov. Scott Walker of Wisconsin, a Republican who has championed the proposed cuts.

The Koch brothers are key promoters of several efforts to destroy American democracy and increase the power of their fellow plutocrats, whom they have organized for the purpose.

Sunday, February 20, 2011

I'm not a huge fan of public service unions, but they are one of the few remaining institutions with any ability or inclination to resist the big money oligarchy and speak up for what's left of the American middle class. One of the huge Republican successes of the past thirty years was breaking American private sector unions, mainly by shipping the jobs of union workers overseas, but also by anti-labor laws.

That's why Wisconsin Governor Scott Walker's plan to destroy public sector unions by denying them collective bargaining rights is seen as a threat by many freedom loving Americans. Paul Krugman puts it this way:

What Mr. Walker and his backers are trying to do is to make Wisconsin — and eventually, America — less of a functioning democracy and more of a third-world-style oligarchy. And that’s why anyone who believes that we need some counterweight to the political power of big money should be on the demonstrators’ side.

Walker's plan won't save any money near term and probably not much long term, but that's not the point, says Krugman. The point is power. Power for the super rich.

So it’s not about the budget; it’s about the power.

In principle, every American citizen has an equal say in our political process. In practice, of course, some of us are more equal than others. Billionaires can field armies of lobbyists; they can finance think tanks that put the desired spin on policy issues; they can funnel cash to politicians with sympathetic views (as the Koch brothers did in the case of Mr. Walker). On paper, we’re a one-person-one-vote nation; in reality, we’re more than a bit of an oligarchy, in which a handful of wealthy people dominate.

Given this reality, it’s important to have institutions that can act as counterweights to the power of big money. And unions are among the most important of these institutions.

You don’t have to love unions, you don’t have to believe that their policy positions are always right, to recognize that they’re among the few influential players in our political system representing the interests of middle- and working-class Americans, as opposed to the wealthy.

Is there much hope for resistance? Not much, I suspect. By doing enough to save the country from economic collapse, but not enough to revive it, Obama gave Republicans a perfect opportunity to counterattack and shift the blame for their economic disaster.

I was at dinner the other night with a friend who is a retired chemist and chemical engineer. He started talking about the CO2 we breathe out and how it compared to the amount put in the air by automobiles. He seemed to think that production by cars was relatively insignificant. I'm sorry to say that I didn't have any numbers to compare. I've since tried to check that out.

Our breathing produces somewhat less than about 300 kg per year per person or something like 2.1 x 10^9 metric tons for all 7 billion of us = 2.1 GT/yr.

One barrel of average crude oil is responsible for about the same amount as a person breathes out in a year - about 315 kg of CO2. the world currently uses about 70 million barrels per day x 365 days = 8 GT per year.

If we combine all fossil fuels and cement production, we add 30 GT of CO2 per year.

So our breathing is a relatively small part of our contribution of CO2 to the atmosphere, but humans, numerous as we are, are a small part of the total biosphere. If we take all respiration, from all living things, about 700 GT of CO2 are produced each year. About half of that comes from autotrophs (plants and other photosynthesizers) and half from heterotrophs - the rest of life. Photosynthetic organisms consume nearly twice as much CO2 as they produce, so respiration and photosynthesis are roughly balanced. Cutting down tropical forests and other efficient carbon consumers changes the balance in favor of respiration however, and deforestation contributes about 7 GT/yr additional CO2 to the atmosphere.

All told, the human effects contribution to annual CO2 production is only about 6% of the total. It's not dominant, but it has been enough to shift the balance and lead to a slow but continuing buildup of CO2 in the atmosphere - roughly one half of a per cent per year.

Bullying in schools has usually been considered a pathology, perhaps the result of trauma suffered by the perp. Primatology suggests otherwise. Competition for status is prominent among many of our close animal relatives, and that status usually confers reproductive advantages vital to the (genetic) struggle for existence. New studies indicate that high school is not so very different, as reported by Tara Parker-Pope in the New York Times.

For many teenagers navigating the social challenges of high school, the ultimate goal is to become part of the “popular” crowd.

But new research suggests that the road to high school popularity can be treacherous, and that students near the top of the social hierarchy are often both perpetrators and victims of aggressive behavior involving their peers.

The latest findings, being published this month in The American Sociological Review, offer a fascinating glimpse into the social stratification of teenagers. The new study, along with related research from the University of California, Davis, also challenges the stereotypes of both high school bully and victim.

Highly publicized cases of bullying typically involve chronic harassment of socially isolated students, but the latest studies suggest that various forms of teenage aggression and victimization occur throughout the social ranks as students jockey to improve their status.

The findings contradict the notion of the school bully as maladjusted or aggressive by nature. Instead, the authors argue that when it comes to mean behavior, the role of individual traits is “overstated,” and much of it comes down to concern about status.

This probably doesn't shock those who remember high school, or at least the movie Mean Girls.

In our primate relatives, these contests may involve alliances and strategy, but they are settled by violence. In high school, violence happens, but a mean rumor or facebook picture might do the trick.

If bullying isn't a pathology, does that mean we ought to tolerate it? I don't think so. Murder, robbery and rape, history suggests, are pretty "natural" too, but we don't tolerate them. It does mean that our strategies for combatting it need to be rethought.

Most bullying takes place among those competing most directly for status, and the closer one gets to the pinacle of popularity, the more likely one is to be victim and perp. At the very top, though, bullying is neither faced much nor perpetrated - there isn't any payoff in it. Mean girls fans may recall that the Lindsay Lohan character was golden until she stepped on the alpha female's toes (by dating her ex).

Of course the meek and weak do become incidental victims - probably mostly of those who lack the status or other capabilities to challenge the elite. Despite certain memes propagated in Glee, picking on the High School Quarterback is rarely a good strategy - if he doesn't kick your ass, the rest of the football team will.

I myself wasn't bullied much in high school. I have occasionally thought that that might be because of my status as ace member of the chess team, but more plausible was the fact that I was a low value target - mostly a non-competitor in the status wars.

Saturday, February 19, 2011

It's not too unusual for genius to be accompanied by a touch of paranoia, and sometimes that paranoia consumes their life. Goedel reputedly starved himself to death for fear that someone was poisoning his food.

Bobby Fisher probably had more excuse for paranoia than most. The FBI was watching him, or at least his family. His telephone was tapped when he was only twelve. The FBI was still hot on his trail seven years later when he had become one of the strongest chessplayers in the world. And the Russians were conspiring against him too. They had, in fact, staffed a whole secret laboratory of psychologists and grandmaster chess players just to probe his psychology, his chess, and potential weak points.

Thursday, February 17, 2011

The year cranking up could be a big one - we can hope it's a big one, with nothing yet to show for the LHC. If the LHC really finds nothing, chances of anybody building the next super accelerator any time soon might be close to zero.

Tyler Cowen is selling a new electronic micro book called The Great Stagnation. It’s a tiny book – essentially just an essay – but it is cheap, $3.99 on Amazon. I like his subject, summarized in the subtitle: How America Ate All The Low-Hanging Fruit of Modern History,Got Sick, and Will (Eventually) Feel Better.

There are a number of interesting ideas, but I liked the last few chapters better than the first. In fact, it didn’t take long for my first symptoms of indigestion to set in.

He has a graph at location 142 tracing growth in median US family income from 1945 to 2007. There are two lines on the graph, one labeled actual, the other labeled “if it had kept pace with GDP per capita.” The graph shows almost steady growth in the GDP per capital line, with median family income faltering and falling well-behind after the early 1970’s. So far, so good, but next he creates a muddle.

You can see the rate of growth of per capita median income slows down…”

Say What?

Do you mean median or per capita? He wants to make the case that median family income is the best measure of economic progress, but then he tries to conflate two measures which he has already shown diverge. There are at least two reasons median income could grow a lot more slowly than per capita GDP: either median family size is decreasing or a larger share of the economy is going to some part of the public other than the median. Neither helps make his case that the real problem is slowing of economic progress. Both happen to be true – families are smaller and the rich are a lot richer.

Cowen’s second graph (location 193), of rate of innovation per billion people since the dark ages is even more problematic. A relatively minor fault is the unreadable lower axis labeling. More to the point are the questions of how such innovation is measured, and the relevance of the per capita divisor. It shows, says Professor Cowen, this measure peaking 1873 and declining exponentially ever since. Pullee-f******-ze!

Far more reasonably, he adds that innovation has become more difficult and expensive. This is certainly true in many fields, but he adds “meaningful innovation has become harder … which means a lower and declining rate of return on technology.” This claim is largely bogus, for a reason which any economist ought to grasp: economy of scale. An innovation in 1800 would likely spread very slowly and accrue benefits only very locally to the inventor, but Steve Job’s latest innovations conquer the world in a heartbeat and he is getting plenty of return on investment.

I like his next point better: “Contemporary innovation often takes the form of expanding positions of economic and political privilege, extracting resource from the government by lobbying, seeking the sometimes extreme protections of intellectual property laws, …” Though I think he goes a bit overboard when he throws Gucci handbags into that mix. This isn’t exactly a new trend, though. Most innovations, from agriculture to the industrial revolution, built and expanded bastions of privilege. Innovations that benefit all tend to be swallowed up by Dr. Malthus.

Cowen has some concerns about measures of productivity, especially the component due to government.

So here is Prof C’s theorem:

1. The larger the role of government in the economy, the more the published figures for GDP growth are overstating improvements in our living standard.

His point, I gather is that production of government goods is valued at cost, a cost which is not based on market values. Thus a billion dollar bridge to nowhere counts as just as much production as a billion dollar research investment that cures cancer. That problem doesn’t arise in the private sector, since we have the price mechanism to sort things out, which is why we know that a billion dollars spent on one guy’s really nice house in India was a more worthwhile endeavor than using the same money to buy a few hundred million healthy meals for hungry Indian children.

Or did I miss some crucial point here?

There is the trivial point that some goods are more critical than others. Deprive the billionaire of food, and eventually his next meal might be worth as much to him as that billion dollar house. Cowen’s problem, I guess, is that he doesn’t trust the political process to allocate resources optimally. Me neither. Only I feel the same way about the market.

For me, the best and most interesting part of his essay is the part on health care. One very striking fact is the relatively low correlation between health care expenditures and objective measures of health outcome: countries that expend a small fraction of what we do on health care have comparable life expectancies, infant mortality, and other such measures. Another fairly familiar fact is that these expenditures are disproportionately for the elderly. The most fundamental problem, perhaps, is the difficulty of judging the value of the care the medical system offers you.

I have on numerous occasions been subjected to extensive amounts of ionizing radiation because a physician thought that I needed it for his diagnosis. In most cases, the upshot was, “good news, you are fine.” In no case was a life threatening and treatable condition found and corrected as a result. The net result: temporary reassurance at the cost of a life shortening dosage of radiation – and money in some medical pockets.

I will briefly mention a few other points that he makes at some length. Inflation adjusted educational expenditures per student have roughly doubled in the last 35 years, but student performance has not notably improved. The internet has become hugely important in our lives and businesses, but in terms of revenue and jobs, it’s a relatively small part of the economy. Multi-billion dollar companies run with a few hundred employees.

Cowen then goes into his basic argument that we had all come to expect too much economic progress, because we had gotten used to it, and that we ran into a wall where technology stopped being the magic breadbasket. So far I’m with him. Next, he extends his idea to explanation of the financial crisis. It’s everybody’s fault he says, we all got to overconfident. Not utterly false, but so encrusted with falsehood as to be deeply misleading.

Most people, including both homebuyers and ordinary investors have neither the resources nor access to the knowledge to independently assess the state of credit markets. They relied on those whose job it was to assess those risks and who had vast resources at their disposal to do so: the investment banks, the ratings agencies, and finally, the federal government regulators. Those people bear the direct responsibility, not Cowen’s vague “all of us.” Equally culpable, perhaps even more culpable, were the economists who sold the lie that all of the foregoing relied on and shuffled their responsibilities on to: the notion that the magic of the market always knew best. Cowen glosses over one crucial detail: those in position to know the most got rich, even extremely rich, selling the lies.

Cowen’s most substantial claim is that the current economic disaster is not (mainly, anyway) due to a failure of aggregate demand, but to a lack of technology to exploit.

Our author naturally has some ideas for fixing the future. He leads with

1. Raise the social status of scientists.

As a scientist, I would hate to dispute this, but I would settle for just undoing the Republican Party’s current plans for gutting the US basic science program. Scientists' status in the US isn’t terribly low, so far as I can tell, and Nobel Prizewinners, so they say, even rate groupies – a circumstance unlikely to improve their productivity.

Another comment adds that we might find something to learn, he says, from the way Japan has handled it’s slow growth economy.

We need to be prepared for a recession that could last longer than we are used to, says the Prof, and beware the next crop of low hanging fruit when we find it – it might turn out to be toxic too.

Saturday, February 12, 2011

Overall, a pretty good movie. Naturally not terribly historically accurate says Christopher Hitchens - Edward VIII was a far more egregious Hitler loving facist than the movie's vague hints suggest, Churchill was his guy all the way, and George VI was another appeaser. The family is a bunch of Germans, after all.

Tuesday, February 08, 2011

Q (Banerjee asks): Rainbow phenomena are predicted very accurately assuming spherical raindrops. But falling raindrops do not remain spherical because of aerodynamic effects. What is the shape of a falling raindrop and what are the effects of that shape on rainbows?

First: about raindrop shapes. The smaller ones (1mm or less) are pretty spherical. Bigger ones tend to a top-half of the hamburger bun shape, see e.g. here. Those bigger than about 4 mm tend to get ripped apart by aerodynamic forces.

Let’s start with ordinary rainbows from spherical drops. We have mostly noticed that the Sun is always at our back when we see rainbows, and if have played around a bit with sprayers on hoses. that we can get complete circular rainbows under the right circumstance. Descartes seems to have been the first to study rainbows systematically, so let’s quote from him, via this marvelous NCAR document: About Rainbows. [You will want to look at the picture in the link]

He writes:"Considering that this bow appears not only in the sky, but also in the air near us, whenever there are drops of water illuminated by the sun, as we can see in certain fountains, I readily decided that it arose only from the way in which the rays of light act on these drops and pass from them to our eyes. Further, knowing that the drops are round, as has been formerly proved, and seeing that whether they are larger or smaller, the appearance of the bow is not changed in any way, I had the idea of making a very large one, so that I could examine it better.

Descartes describes how he held up a large sphere in the sunlight and looked at the sunlight reflected in it. He wrote "I found that if the sunlight came, for example, from the part of the sky which is marked AFZand my eye was at the point E, when I put the globe in position BCD, its part D appeared all red, and much more brilliant than the rest of it; and that whether I approached it or receded from it, or put it on my right or my left, or even turned it round about my head, provided that the line DE always made an angle of about forty-two degrees with the line EM, which we are to think of as drawn from the center of the sun to the eye, the part D appeared always similarly red; but that as soon as I made this angle DEM even a little larger, the red color disappeared; and if I made the angle a little smaller, the color did not disappear all at once, but divided itself first as if into two parts, less brilliant, and in which I could see yellow, blue, and other colors ...

When I examined more particularly, in the globe BCD, what it was which made the part D appear red, I found that it was the rays of the sun which, coming from A to B, bend on entering the water at the point B, and to pass to C, where they are reflected to D, and bending there again as they pass out of the water, proceed to the point ".

What happens when see that bit of color from a drop is that a ray of light, coming from more or less behind us, has entered the spherical drop, been bent slightly by refraction as it enters, been reflected from the back of the droplet, been refracted again as it leaves, and ultimately entered our eye. The important point is that 42 degree angle that Descartes observed – the reflected rays come out at an angle of 42 degrees to the incident rays. Imagine, if you will, a straight line drawn from the Sun, through your head, and out into the beyond. You will noticed that the observed position of the rainbow is along the 42 degree arc about that axis from Sun through head.

The other important thing Descartes noticed was that slightly different angles correspond to different colors of light. Some colors are refracted more than others, and it’s that color separation that produces the rainbow of colors. It’s also possible for rays of light to bounce twice inside the droplet before exiting – such double reflections produce a fainter, color reversed rainbow at about 50 degrees.

Banerjee asked what effect the aerodynamic distortion of the drops has on the rainbow. The most common such distortion observed is a flattening of the drops. That flattening is believed to be responsible for the fact that for low Sun angles the edges of the rainbow are sometimes brighter than the top. The flattening of the big drops (little drops remain nearly spherical) causes the rainbows rays to disperse and leak out of the drops.

Another point worth mentioning is that you should notice that the region inside the arc is noticeably brighter than the outside. This is another rainbow effect, due to the fact that:

When one studies the refraction of sunlight on a raindrop one finds that there are many rays emerging at angles smaller than the rainbow ray, but essentially no light from single internal reflections at angles greater than this ray. Thus there is a lot of light within the bow, and very little beyond it. Because this light is a mix of all the rainbow colors, it is white. In the case of the secondary rainbow, the rainbow ray is the smallest angle and there are many rays emerging at angles greater than this one. Therefore the two bows combine to define a dark region between them - called Alexander's Dark Band, in honor of Alexander of Aphrodisias who discussed it some 1800 years ago!

This quote, and most of the content of the present post, are taken or adapted from the NCAR reference cited above.

Saturday, February 05, 2011

Q: Why do (some) clouds keep their shape for a long time and do not disperse quickly?[asks Wolfgang]

If we watch clouds, one thing we notice is that most clouds keep changing their shapes. They grow and shrink, form and evaporate. A few, however, don't. Both processes are driven by motions in the atmosphere. I will consider one process of each type, though there are many more.

The most common shape changer might be the fair weather cumulus. These are the kind of clouds that appear especially on warm and sunny summer days with little wind. Typically they form in the early to mid-afternoon and have a flat-bottomed, roundish shape and a puffy top, without great thickness. Individual clouds are rather short lived, usually less than an hour. After the sun warms the ground and the air in contact with it, puddles of warm and hence lighter air form near the ground, begin rising, and eventually form columns of rising air. Typically, this near ground air is both warm and moist, and as the air rises, it cools, and the moisture in the cloud eventually reaches a level and temperature at which it begins to condense. This level forms the base of the cloud. See, for example, Wikipedia on the Lifted Condensation Level.

Such clouds tend to be transitory, because the pool of warm air that fed the rising column of air runs out, and its moisture is mixed away and its heat radiated away and it falls again. If there are turbulent winds aloft, the pool of warm air is torn apart, mixed with local dry air, and the cloud fragments and vanishes.

One shape maintaining cloud is the so-called orographic cloud. This kind of cloud forms especially over mountains when there is a steady wind aloft. What happens in such clouds is that a stream of air is forced upward as the wind blows over the mountain and that upward motion cools the air and causes it to condense as it rises. As the air flows beyond the mountains, it falls again and the moisture evaporates. The orographic cloud is like the wave in a fast moving stream that forms over a shallowly submerged rock - the water keeps moving past, but the wave, and the orographic cloud, stays in one place.

Here is a link to a very nice orographic cloud: My part of New Mexico often has rather spectacular orographic clouds. Sometimes the air flowing over the mountains will have several moist layers with drier layers in between - in such cases orographic clouds can stack up like pancakes, one on top of another.

Other cloud formations maintain their shapes to a greater or lesser degree - thunderclouds, frontal clouds, hurricanes. In each case, the key to stability or instability is the underlying dynamical process. Is the stream of energy feeding the cloud steady or unsteady, transitory or lasting?

The original atmosphere of our planet was almost certainly lost to space in the early excitements of planetary formation and bombardment. The air we have today can be considered to be the accumulated out gassing of the planet - Terran afflatus, so to speak. The rocks out of which our planet formed contained small amounts of various gasses which have been gradually released by physical and chemical volcanic processes.

Q: Why is the sky blue?

The blueness of the sky, where the sky still is blue, is evidence for the molecular composition of the atmosphere. Because the atmosphere consists of myriads of these little tiny guys bouncing around randomly, their random motions produce random fluctuations in the density of the air at very small scales. The expected size distribution of these fluctuations can be calculated, and it turns out that most of them are several times as small as the wavelength of visible light. Light scatters from density fluctuations (or, more precisely, from the index of refraction fluctuations resulting therefrom) and the expected amount of scattering can be calculated.

It is found that for the appropriate size fluctuations, scattering varies with the fourth power of frequency (inverse fourth power of wavelength) so that shorter wavelengths are scattered a lot more. Blue light is the shortest, and is scattered the most. The blue light of the sky is a haze of light scattered from the fluctuations in molecular density.

Ultraviolet light is shorter still, and scattered even more, which is one reason that you can get a sunburn outside even if you are sitting in the shade of an awning - there is enough scattered UV to give you a burn.

If visible light was several times shorter in wavelength, or the density variations several times larger, scattering would be more democratic among the wavelengths

Q: Where do clouds come from? Were there clouds in ancient times?

If you spend a bit of time watching the sky you notice that some clouds appear to come from somewhere over the horizon, but others seem to form out of thin air. Well, all clouds do form out of thin air, but some last long enough to blow from one side of the horizon to another.

The way clouds form out of thin air is that water vapor in the air condenses to form tiny drops of water, or, sometimes, if it's cold enough, tiny particles of ice. Nearly everyone has seen the first process - if you watch steam condense from a tea kettle, or a steam engine, or breathe out on a cold day, or in a walk in freezer. If the air is clean enough, it's really quite hard to form these little droplets or (especially) ice crystals. Water vapor likes to have a little bit of "dirt" of some kind or other to condense on - something with some electrical charges sticking out to attach to the polar water molecules.

Bits of such "dirt," suitable for the formation of water droplets, called cloud condensation nuclei, or CCNs, are ubiquitous in the lower atmosphere. Tiny grains of sea salt from breaking wave, the chemical exudates of trees and factories, and dust from the ground all work well. Nuclei suitable for the condensation of ice crystals (ice condensation nuclei) must meet a tougher standard, because ice crystals are very picky about how they form. When water vapor reaches the critical amount in the atmosphere, there is usually enough CCNs for clouds to form. For ice clouds, this isn't necessarily so. That's the reason that we often see giant contrails form in the wake of jet aircraft. There might be enough water vapor for a cloud to form, but not enough ice condensation nuclei. The exhaust of the jet engine seeds the upper atmosphere with enough condensation nuclei to produce sometimes giant clouds - the US cleared rater noticeably in the days after 9/11 when no planes flew.

So, how about our second question? Were there clouds way back when? For sure there were, since we see eroded sedimentary rock even from extremely ancient times, rock that could only have been produced by running water, which had to get there from the sky, in the form of rain or snow from clouds.

Friday, February 04, 2011

The IOWA legislature was debating some legislation to stigmatize or otherwise harass gay parents, and a nineteen year old student (raised by gay parents)decided to share his experience in testimony against the bill. His testimony went viral and was widely praised. Steve Landsburg, blogger, economist, and a favorite punching bag of mine thought this would be a good occasion to demonstrate that he is obnoxious - he is good at finding such occasions, and published this critique.

Some people claim (perhaps rightly, perhaps wrongly, perhaps absurdly — I lean toward the latter) that gay people, on average, are less successful as parents. In a video that’s begun to go viral, University of Iowa engineering student Zach Wahls attempts to refute this notion without offering a shred of evidence beyond a single cherry-picked case (his own) to prove that children of gay parents sometimes turn out just fine (except, perhaps, for their ability to reason):

His complaint seems to be that Zach presented a personal story rather than some published statistics. More amusingly, Landsburg goes on to blame Zach's English professors, without, of course, citing so much as any bit of fact or experience.

What’s particularly disturbing to me is all the chatter about how eloquent this kid is, as if eloquence in the service of intellectual misdirection were somehow something to be admired. Odds are, this pernicious message was reinforced by the college writing courses that I complained about in Chapter 23 of The Big Questions.

Zach Wahls gives every appearance of being a likable and accomplished 19-year-old with a good command of the language, and, like many 19-year-olds much of the time, not much to say. Fortunately, that’s a curable condition. I’m counting on his engineering professors to undo whatever damage the English department has managed to inflict.

How dumb do you have to be to blatantly commit the same rhetorical error that the target of your rhetoric is accused of? As a point of fact and statistics let's consider the relative performance of various majors on the Graduate Record Exam. Note that English majors finish second only to Philosophy majors in the most relevant categories, verbal reasoning and analytical writing, though they do far less well in the quantitative. Economists tend to be solidly mediocre in every category.

I have to admit that I sometimes feel a twinge of guilt about bashing the old Stevadoreo. Maybe he has some intellectual defect that keeps him from seeing the relevance of the personal testimony of somebody like Zach - this is a guy who claims to evaluate his happiness by checking to see if he's acting happier than the people around him, after all - he surely has some kind of defect. So Steve, if you do have some kind of autism spectrum disorder that blinds you to much of human nature, my apologies and sympathies. But you still shouldn't really write about stuff you know nothing about. And you ought to check your arguments for internal consistency.

Thursday, February 03, 2011

Is this the same kind of question as "Are you happy?" Steve Landsburg thinks so, but I have a different opinion. The title question pretty clearly refers to some external standard, and in particular to other people, almost certainly others of your sex and age group - adult or child. The second question clearly refers to a purely internal standard, and almost certainly to an absolute rather than relative sense. I could be pretty unhappy even if I was slightly less unhappy than I was yesterday - or contrarywise.

So how could an ostensibly bright guy like Landsburg - here I am referring to an external standard of IQ tests, professional accomplishment, etc - make such a dumb error of category?

I don't know, but I have a guess - systematic intellectual dishonesty.

All this is apropos of a couple of Landsburg posts, each of which, like Tolstoy's unhappy families (Anna Karenina), is unhappy in its own way.

Tuesday's Burg deals with freedom and prosperity, with freedom being measured by somebody's indices of political freedom, civil liberties, and economic freedom respectively versus prosperity being measured by per capita GDP. These results are presented in three graphs.

Each index shows some correlation between freedom and prosperity, but the economic freedom correlation is clearly the strongest. Landsburg concludes:

Political freedom and civil liberties are good things. I endorse them. But as far as human happiness goes, capitalism is an even better thing.

Now I find equating capitalism with economic freedom a bit dubious, since some forms of capitalism don't really offer a lot of economic freedom, but if we consider capitalism in the Smithian ideal, maybe so. The second equation, between per capita GDP and human happiness is a laugher, though. It's when challenged on this that the Burg steps into Preposteroland, referring us to this older post.

I don’t think self-reported happiness tells us anything at all about actual happiness. If a pollster asks me “Are you happy?”, the question I’m going to answer is “Are you happier than your friends seem to be?”. Regardless of the ambient level of happiness, about half of us will always answer “No”.

Now this is just goofy. If the doctor prods him and asks "does this hurt" is he going to answer the question "do I hurt less than my friends seem to?" If he wakes up puking, does he ask himself the question "do I seem sicker than my friends?"

And next:

A colleague of mine observes that the average American man is about 2 inches taller than a hundred years ago. But you’d never learn that from a survey that asks people “Are you tall?”. That’s because a 5′9″ man would probably have answered “yes” a hundred years ago and “no” today. And likewise, people might be far happier today than a hundred years ago, but you’d never learn that from a survey that asks “Are you happy?”

The thing is, his happiness analysis doesn't even meet his own standard. Most of us, especially if we travel, are exposed to people of a wide variety of levels of prosperity. If we ask ourselves, do these people seem to be as happy as the people I meet of some significantly different level of prosperity, it's pretty clear that wealth doesn't necessarily make one happy, and that poverty, short of desperation, doesn't necessarily make one unhappy.

I am reminded of a Tennessee Williams quote, which I can't find exactly, but has the following sense: Before my first big theatrical success, I was poor, lived in a miserable apartment, didn't know where the rent money was coming from, but I was happy. After the big Broadway success, I was rich, and livid in luxury, but I was miserable.

I suspect that Landsburg dismisses these rather obvious facts because they don't fit this theory. Any other guesses?

The latest winter storm brought us about 3 inches of snow and far colder weather (very slightly below zero Fahrenheit) than we are used to in Southern New Mexico. As a result, all schools and many government agencies are shut down.

Say what? Three inches of snow shuts down the government?

It's a bit more complicated. The reason schools, etc are shut down is that we don't have enough electricity to go around. If the schools etc. opened, somebody else, businesses and homes, would lose power. As it is, we are subject to "rolling brownouts" - my wife turned on a space heater last night and it blew the circuit breaker for the room.

Wednesday, February 02, 2011

Latest events make it pretty clear that the Army is complicit in the attacks on the pro democracy demonstrators in Egypt. What happens next is far less clear. Anti-Mubarak forces will probably need better weapons than rocks if they hope to push him out now. The US has provided Mubarak an Army that should have little trouble quelling the revolt - if the Colonels decide to stick with him.

Well, yes. If Israel were surrounded by economically and culturally vigorous Arab democracies instead of rotten autocracies, the apartheid state it is currently trying to establish would be far less tenable and for less acceptable to the world.

And, no. Because if that should happen, the excuse for the apartheid state would vanish, and it might actually reform itself.

Musically I'm an ignoramus. I don't know a dominant from a mediant - or at least I didn't before last night. I signed up for a Community College course in the Beethoven Symphonies, and last night was my first class - I missed the first week, it seems. The instructor's approach is to begin by explaining the musical elements and illustrating them with brief excerpts - dual themes with variations, sonata form, minuet and trio, etc., etc. Unfortunately I'm a bit too slow to pick all that up, and my musical memory is not so hot either.

He adds another layer to this sort of syntactical analysis - a sort of Symphony as novel layer. (I liked his remark that Beethoven found the Symphony as a book of four short stories and left it as a novel with four - or five - chapters.) I was a bit less thrilled with the particular novel he found, though. I suppose it would be too obtuse to fail to see Beethoven's Fifth as something other than threat, struggle, and ultimate triumph, but somehow, when it was reduced to the C Major theme whacking and ultimately abusing the now broken and cowering C Minor theme it felt a bit too pat and personal. Especially when the subject turned orchestral "hugs" and "embraces." Again, it seemed almost TMI, like learning the details of your parents' sex lives.

Still, I do love the Fifth Symphony, even if he kept interupting with voice over reminders of the musical structures in question. Perhaps enough will stick that I gain a deeper appreciation of the music.

Did I mention that I tend to suffer from semi-obsessive musical thoughts - there often seems to be a sort of damned juke box playing in my head. It may not be a promising sign that when I woke up at two AM, the tune that was on was not Beethoven but Lady Gaga's Bad Romance.